KR20180031123A - Engine mount - Google Patents

Abstract

The present invention relates to an engine mount. An objective of the present invention is to provide an engine mount which can simultaneously improve rattle noise by a movement of a membrane in a large displace movement condition such as driving on an uneven road, noise by creation of bubbles in a fluid, a booming problem during acceleration driving, a lack of a damping force by insufficiency of flow resistance between an upper fluid chamber and a lower fluid chamber, and an idle low frequency vibration problem by the lack of a damping force. To achieve the objective, the engine mount is a fluid-sealing mount comprising: an insulator forming an upper fluid chamber; an orifice lower plate which is assembled on a lower side of the insulator, and has an annular inertia track; an orifice upper plate assembled on an upper side of the orifice lower plate to cover the inertial track to form the upper fluid chamber with the insulator; a diaphragm assembled on a lower side of the orifice lower plate to form the lower fluid chamber; and a membrane inserted into a membrane storage space between the orifice upper plate and the orifice lower plate. A fluid penetration hole connecting the membrane storage space and an internal space of the inertial track is formed on the orifice lower plate to allow a fluid of the upper and the lower fluid chamber to flow into the membrane storage space through a hole of the orifice upper plate and a hole of the orifice lower plate and then move to the internal space of the inertial track.

Description

Engine mount {Engine mount}

The present invention relates to an engine mount, and more particularly, to an engine mount, which is capable of preventing rattling due to membrane flow, occurrence of bubbles in a fluid due to membrane flow, To an engine mount capable of simultaneously reducing the damping force due to the flow resistance between the liquid chambers and the idle low frequency vibration problem.

Generally, when a powertrain including an engine and a transmission of a vehicle is mounted in an engine room, the powertrain is mounted to be supported by a subframe by an engine mount, a transmission mount, a roll load, Is coupled to a body frame that forms an engine room.

In order to effectively reduce vibration and noise transmitted to the vehicle body, the characteristics of the mount are required to have low damping at low vibration speed and low dynamic spring constant at high vibration speed.

In order to satisfy such a characteristic, a fluid enclosed type mount in which a fluid is encapsulated in a lower part of a rubber insulator is used. In the case of an engine mount, a fluid encapsulated type structure is usually used.

The fluid-filled mount has a structure capable of appropriately attenuating vibrations over a wide range of frequencies, such as low-frequency / high-amplitude vibrations or high-frequency / low-amplitude vibrations, 1, a conventional engine mount structure will be described as follows.

As shown in the figure, a conventional fluid-filled engine mount 1 includes a center bolt 10 fastened to the engine side, an inner core 10 having the center bolt 10 inserted therethrough, A rubber insulator 30 formed integrally with the inner core 20 by a vulcanization molding process and an insulator 30 assembled to surround the insulator 30 by inserting a lower portion of the insulator 30, An outer pipe 40 that is fastened to the vehicle body through a mounting bracket that is fastened to the lower end of the insulator 30 and a diaphragm 50 that is assembled to the bottom of the insulator 30; An orifice upper plate 60 assembled on the upper side of the orifice upper plate 50 and a membrane 80 inserted between the orifice upper plate 70 and the orifice lower plate 60, .

The space between the insulator 30 and the orifice lower plate 60 and the membrane 80 becomes the upper liquid chamber 2 in which the fluid is sealed and the lower side of the upper liquid chamber 2 is provided with the membrane 80 and the orifice lower plate 60 and the lower liquid chamber 3 in which the fluid is enclosed is a space formed by the diaphragm 50 and a space defined by the membrane 80 and the upper liquid chamber 2.

An inertia track 61 is formed at the periphery of the orifice lower plate 60 so as to be annularly arranged along the circumference of the upper liquid chamber 2 and the lower liquid chamber 3, (61) has an upper side covered with an orifice upper plate (70).

The inner passage of the inertia track 61 has a structure connected to the upper liquid chamber 2 by an opening hole 71 formed through the orifice upper plate 70. When the inner volume of the upper liquid chamber 2 decreases, The fluid in the liquid chamber 2 is moved to the inertia track 61 through the opening hole 71 of the orifice upper plate 70.

A reinforcing plate 81 made of a steel material is inserted into the membrane 80.

In the fluid-filled engine mount 1 constructed as described above, when vibration is transmitted from the engine, the inner core 20 and the insulator 30 are deformed to change the volume of the upper liquid chamber 2, and the amount corresponding to the changed volume Of the fluid flows from the upper liquid chamber 2 to the lower liquid chamber 3.

2, the fluid flows into the annular inertia track 61 through the opening hole 71 of the orifice upper plate 70 and then flows along the inertia track (see arrow A) or through the membrane 80) and the orifice upper and lower plates 60, 70 (see arrow B).

That is, the impact from the upper side is transmitted to the fluid in the upper liquid chamber 2, and the impact at this time is converted into a little heat energy in the course of the passage of the fluid through the passage, The impact quantity is secondarily attenuated.

If the amount of fluid corresponding to the deformation volume of the inner core 20 and the insulator 30 is larger than the amount of movement that can pass through the gap between the membrane 80 and the upper and lower plates 60 and 70, When the above vibration occurs, the fluid flows along the annular inertia track 61 without passing through the gap between the membrane 80 and the upper and lower plates 60 and 70. At this time, A large damping force is generated due to resonance with the fluid in the track 61.

On the other hand, when vibrations on the high-frequency urine are input from the engine, the displacement of the internal displacement is within the range in which the membrane 80 can move, and the amount of fluid corresponding to the deformation volume of the inner core 20 and the insulator 30 is relatively The fluid flows from the upper liquid chamber 2 to the lower liquid chamber 3 through the gap between the membranes 80 having relatively low flow resistance without passing through the annular inertia track 61 having a large flow resistance. The vibration is damped while passing in a short time.

Such a fluid-filled engine mount is intended to attenuate a specific frequency and to reduce dynamic characteristics that can not be solved by existing rubber types. In recent years, in order to increase the insulation rate in a high frequency band, a fluid- Engine mounts are being developed and mass-produced.

In the double orifice structure, a secondary nozzle 72 having a predetermined height for connecting the upper liquid chamber 2 and the lower membrane 80 is provided at the center of the orifice upper plate 70, 61), as well as a secondary orifice action through which the fluid enters and exits through the secondary nozzle 72 (the fluid acts independently of the orifice action through the membrane gap), as well as attenuating vibration through the primary orifice action ) To reduce the dynamic characteristics.

Improving ride performance by suppressing power train vibration by damping low frequency bands during primary orifice operation and improving NVH (noise vibration) performance by increasing insulation rate by reducing dynamic characteristics of high frequency band during secondary orifice action .

On the other hand, various types of engine mounts are known in terms of membrane type and shape.

In addition, in the engine mount, there are various reasons for the occurrence of the joint. The type and shape of the membrane, the size, the presence of the reinforcing plate, and the height of the nozzle are known.

Therefore, in order to reduce the occurrence of joints, various improvements have been proposed in consideration of the above factors. However, since the above factors are factors that change the dynamic characteristics of the engine mount, There is a limit in reducing the amount of water.

In some cases where the joints are generated in the engine mount, for example, air bubbles (bubbles) are generated in the fluid due to the internal vacuum pressure generated by repetitive excitation, and then a joint may occur during the extinction.

That is, the internal pressure of the liquid chamber changes due to the excitation, and air bubbles are generated in the fluid due to the generated vacuum pressure, and the air bubbles disappear while the internal pressure is reversed.

In addition, the membrane may move due to the internal pressure, and may be caused by a shock between the membrane and the orifice (nozzle) and between the lower plate.

That is, fluid pressure in the liquid chamber is generated by the excitation, and when the pressure acts as a load on the membrane, the membrane flows, and rattle joint may occur while striking the orifice and the lower plate.

Such a rattle joint can be improved by reducing the gap between the membrane and the orifice and the lower plate.

However, when the gap between the membrane and the orifice and the lower plate is reduced, the problem of booming at the time of acceleration running may be deteriorated.

More specifically, in the case where the road is a rough road, the membrane of the engine mount has a large lateral flow, and the flow of such a membrane increases the rattle joint.

In order to reduce such a rattle joint, the gap between the membrane 80 and the orifice upper and lower plates 60 and 70 as shown in Fig. 4 must be reduced.

However, at the time of accelerated traveling, the engine mount 1 and the membrane 80 behave in the direction of the urine. At this time, when the gap is small, the suction performance may be deteriorated due to the membrane restraint.

The gap between the membrane 80 and the orifice upper and lower plates 60 and 70 must be increased in order to solve the problem of booming in such an accelerated traveling.

Therefore, there is a contradiction in the method of improving the jointing problem during running with the unevenness and the method of improving the booming problem in the acceleration running. In setting the gap between the membrane 80 and the orifice upper and lower plates 60 and 70, As shown in FIG.

In addition, when the bump is generated due to the large flow path resistance between the upper and lower liquid chambers 2 and 3 at this time, the large-displacement behavior of the engine mount 1 occurs when the vehicle is running with the ridges and valleys. The flow resistance between the liquid chambers 2 and 3 must be reduced.

On the other hand, when the flow resistance between the upper and lower liquid chambers 2 and 3 of the engine mount 1 is small when the engine idle is driven, the flow of urine on the membrane 80 appears and the damping force is insufficient. A problem of low frequency vibration appears.

In order to solve the problem in the idle low frequency oscillation, the flow resistance between the upper and lower liquid chambers must be increased.

As described above, there is a contradiction also in the method of improving the noise problem due to bubbles and the low-frequency vibration problem of the idler during traveling by unevenness.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in an effort to solve the above problems, and it is an object of the present invention to solve the above-mentioned problems, and to provide a method and apparatus for preventing rattling, It is an object of the present invention to provide an engine mount capable of simultaneously reducing the damping force due to the flow resistance between the upper liquid chamber and the lower liquid chamber and the idle low frequency vibration problem caused thereby.

According to an aspect of the present invention, there is provided an insulator comprising: an insulator which forms an upper liquid chamber; an orifice lower plate which is assembled to the lower side of the insulator and has an annular inertia track; A diaphragm assembled to the lower side of the orifice lower plate to form a lower liquid chamber, and a membrane inserted into a membrane accommodating space between the orifice upper plate and the lower orifice plate, wherein the upper liquid The fluid in the lower and upper fluid chambers communicates with the inner space of the inertia track on the orifice lower plate so that the fluid can pass through the holes of the upper plate of the orifice and the holes of the lower plate of the orifice to enter the membrane storage space, Fluid It provides an engine mount according to claim gwahol is formed.

According to the engine mount of the present invention, since the fluid passage hole is formed in the side wall of the case housing the membrane, and the through hole is formed in the membrane, the fluid passage hole is formed in the upper liquid chamber and the lower liquid chamber, The fluid moves from the upper liquid chamber to the lower liquid chamber through the expanded through-hole when the membrane expands in the circumferential direction of the membrane, and the flow resistance between the upper and lower liquid chambers may be reduced .

As a result, the improvement of the acceleration traveling booming and the improvement of the idle low-frequency vibration at the time of urine can be maintained, but the membrane flow can be reduced due to the reduction of the gap between the membrane and the case at the large displacement condition, , The flow resistance between the upper and lower liquid chambers and the pressure difference can be reduced, and the occurrence of the bouncing due to the bubbles can be prevented.

1 and 2 are sectional views showing a conventional fluid-filled engine mount having a general orifice structure.
3 is an exploded perspective view showing a conventional fluid-filled engine mount having a double-orifice structure.
FIG. 4 is a view for explaining a jointing problem during traveling and a booming problem during acceleration running in the conventional engine mount.
5 is a cross-sectional view showing a lower portion of an engine mount according to an embodiment of the present invention.
6 is a cross-sectional view taken along the line 'C-C' in FIG.
FIG. 7 is a view for explaining the operation of the engine mount according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

FIG. 5 is a cross-sectional view illustrating the lower portion of the engine mount according to the embodiment of the present invention, and FIG. 6 is a cross-sectional view taken along the line 'C-C' in FIG.

The basic structure of the engine mount according to the embodiment of the present invention is the same as the conventional structure except that the fluid passage hole 62 of the lower orifice lower plate 60 and the through hole 82 of the membrane 80 are additionally formed, There is no difference in comparison with the configuration of the engine mount of Fig.

Therefore, the center bolt, the inner core, the insulator, the outer pipe, and the diaphragm will be described with reference to Figs.

A fluid-sealed engine mount (1) according to an embodiment of the present invention includes a center bolt (10) fastened to an engine side, an inner core (10) through which the center bolt (10) A rubber insulator 30 formed integrally with the inner core 20 by a vulcanization molding process and an insulator 30 assembled to surround the insulator 30 by inserting a lower portion of the insulator 30, An outer pipe 40 that is fastened to the vehicle body through a mounting bracket that is fastened to the lower end of the insulator 30 and a diaphragm 50 that is assembled to the bottom of the insulator 30; An orifice upper plate 60 assembled on the upper side of the orifice upper plate 50 and a membrane 80 inserted between the orifice upper plate 70 and the orifice lower plate 60, .

The space between the insulator 30 and the orifice lower plate 60 and the membrane 80 becomes the upper liquid chamber 2 in which the fluid is sealed and the lower side of the upper liquid chamber 2 is provided with the membrane 80 and the orifice lower plate 60 and the lower liquid chamber 3 in which the fluid is enclosed is a space formed by the diaphragm 50 and a space defined by the membrane 80 and the upper liquid chamber 2.

An inertia track 61 is formed at the periphery of the orifice lower plate 60 so as to be annularly arranged along the circumference of the upper liquid chamber 2 and the lower liquid chamber 3, (61) has an upper side covered with an orifice upper plate (70).

The inner passage of the inertia track 61 has a structure for connecting the upper liquid chamber 2 and the lower liquid chamber 3 and has an opening hole 71 formed through the orifice upper plate 70, The fluid in the upper liquid chamber 2 moves to the inertia track 61 through the opening hole 71 of the orifice upper plate 70 when the inner volume of the upper liquid chamber 2 decreases.

In the fluid-filled engine mount 1 constructed as described above, when vibration is transmitted from the engine, the inner core 20 and the insulator 30 are deformed to change the volume of the upper liquid chamber 2, and the amount corresponding to the changed volume Of the fluid flows from the upper liquid chamber 2 to the lower liquid chamber 3.

2, flows into the annular inertia track 61 through the opening hole 71 of the orifice upper plate 70 and then flows along the inertia track (see arrow A 'in Fig. 2) Or passing through the gap between the membrane 80 and the orifice upper and lower plates 60 and 70 (see arrow B 'in FIG. 2).

In FIG. 6, the arrow 'D' indicates the flow direction of the fluid flowing along the inner space of the inertia track 61, and the upper surface of the membrane 80 is not shown in cross section.

5, the orifice upper plate 70 and the orifice lower plate 60 may be integrally formed with the upper plate 70 and the lower plate 60 so that the membrane 80 can be inserted into a space between both sides of the orifice upper plate 70 and the orifice lower plate 60, And the upper plate 70 and the lower plate 60 serve as a case for accommodating the membrane 80 and restricting the flow of the membrane.

The orifice upper plate portion 70a and the orifice lower plate portion 60a which form the membrane accommodating space in the present invention are case portions in which the membrane 80 is accommodated and the case portion has an orifice An upper sidewall portion 70a and an inner sidewall 60b of the orifice lower plate 60 forming side portions of the inertia track 61 and an orifice lower plate portion 60a for supporting and restraining the membrane 80 from the lower side do.

A hole 72 communicating with the upper liquid chamber 2 is formed in the orifice upper plate portion 70a and a hole 63 communicating with the lower liquid chamber 3 is formed in the lower orifice plate portion 60a have.

In the present invention, the orifice lower plate 60 is provided with a fluid passage hole 62 for communicating the membrane storage space and the inner space of the inertia track 61, and in the preferred embodiment forming the side portion of the inertia track 61 A fluid passage hole 62 may be formed in the inner circumferential side wall 60b of the orifice lower plate 60.

6, the fluid passage holes 62 may be formed on the inner sidewall 60b of the orifice lower plate 60 along the circumferential direction at a plurality of predetermined intervals, Each of the fluid pass holes 62 penetrates the inner sidewall 60b of the orifice lower plate 60 in the radial direction so as to communicate the membrane storage space formed by the upper orifice lower plate 60 and the inner space of the inertia track 61, .

The plurality of fluid passing holes 62 may be formed at equal intervals along the circumferential direction on the inner sidewall 60b of the orifice lower plate 60. [

The plurality of fluid passing holes 62 are located adjacent to the periphery of the membrane 80 at the inner sidewall 60b of the orifice bottom plate 60. [

In the engine mount of the present invention, a through hole 82 penetrating through the membrane 80 is formed. In this case, the through hole 82 may be formed in a small size at the center of the membrane 80.

Hereinafter, the operation of the engine mount will be described with reference to FIG.

First, in the engine mount according to the embodiment of the present invention, a sufficient clearance is provided between the membrane 80 and the case portion (orifice upper plate portion 70a and orifice lower plate portion 60a) The suction performance of the membrane 80 can be maintained by the clearance between the case portions so that the performance against the booming during the acceleration traveling can be ensured (the same applies to the booming improvement structure in the conventional acceleration traveling) .

Further, the membrane 80 can maintain the flow resistance between the upper liquid chamber 2 and the lower liquid chamber 3, thereby improving the problem of idle low-frequency vibration (as in the case of the conventional idle low-frequency vibration improving structure) box).

Next, a description will be given of the behavior and effect of the large displacement when a large displacement occurs, and a fluid flow at a high flow velocity occurs between the upper liquid chamber and the lower liquid chamber.

7A, the fluid in the upper liquid chamber 2 and the lower liquid chamber 3 flows through the hole of the case portion, that is, the hole 72 of the orifice upper plate portion 70a and the lower orifice lower plate portion 60a, Through the holes 63 of the membrane storage compartment and then into the inner space of the inertia track 61 through the fluid passage hole 62 in the membrane storage space.

As the fluid moves through the fluid passage hole 62, the flow resistance between the upper liquid chamber 2 and the lower liquid chamber 3 decreases and the pressure difference between the upper liquid chamber 2 and the lower liquid chamber 3 decreases, The occurrence of bubbles and hence the occurrence of joints can be prevented.

The pressure in the inner space of the inertia track 61 that has passed through the fluid through holes 62 is reduced and the pressure reduction effect (Bernoulli principle) as the fluid moves through the fluid through holes 62 The rubbery membrane 80 is expanded and deformed in the direction toward the fluid passage hole 62, that is, in the radial direction.

7B, the membrane 80 and the orifice lower plate 60 are brought into contact with the inner side surface of the case 80, that is, the inner side wall 60b of the orifice lower plate 60, So that the membrane 80 is restrained and the flow of the membrane is reduced, so that the occurrence of the rattle joint can be prevented.

When the periphery of the membrane 80 is brought into contact with the inner sidewall 60b of the orifice lower plate 60 while the membrane 80 is expanded in the radial direction as described above, .

As the membrane 80 expands in the radial direction as described above, the small through-hole 82 in the central portion of the membrane expands and deforms into a relatively large hole. Through this through-hole 82, The flow resistance between the upper liquid chamber 2 and the lower liquid chamber 3 can be reduced.

As a result, as the flow passage area of the through hole 82 increases, the pressure difference between the upper liquid chamber 2 and the lower liquid chamber 3 can be reduced, and this pressure difference reduction can prevent the generation of bubbles, have.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. And are also included in the scope of the present invention.

1: engine mount 2: upper liquid chamber
3: lower liquid chamber 10: center bolt
20: inner core 30: insulator
40: outer pipe 50: diaphragm
60: Lower orifice plate 60a: Lower orifice plate portion
60b: inner circumferential wall 61: inertia track
62: fluid passage hole 70: orifice top plate
70a: orifice upper plate portion 71: opening hole
80: Membrane 82: Through hole

Claims (6)

An orifice lower plate assembled to the lower side of the insulator and formed with an annular inertia track, an orifice upper plate assembled on the upper side of the orifice lower plate to cover the inertia track to form an upper liquid chamber together with the insulator, A fluid enclosed mount comprising a diaphragm defining a lower liquid chamber and a membrane inserted into a membrane containment space between the orifice upper plate and the orifice lower plate,
The fluid in the upper liquid chamber and the lower liquid chamber passes through the holes of the orifice upper plate and the lower plate of the orifice to enter the membrane storage space and then to the inner space of the inertia track, And a fluid passage hole communicating with the fluid passage hole.
The method according to claim 1,
Wherein the fluid passage hole is formed to pass through an inner sidewall of the orifice lower plate to which a peripheral portion of the membrane comes into contact when radially expanding the membrane.
The method of claim 2,
Wherein a plurality of the fluid passing holes are formed along the circumferential direction on the inner circumferential side wall of the lower orifice plate.
The method of claim 3,
And the fluid passing holes are formed at equal intervals along the inner circumferential side wall of the lower orifice plate.
The method according to claim 2 or 3,
Wherein the fluid passage hole is closed by the periphery of the membrane contacting the inner circumferential side wall of the lower orifice plate when the membrane is radially expanded.
The method according to claim 1,
Wherein a through hole is formed in the membrane so as to penetrate the membrane vertically and extend in size when the membrane expands in the radial direction.

Images